Heparan sulfate-like immunoreactivity in the spinal cord in motor neuron disease

Summary The spinal cords from eight autopsy cases of sporadic motor neuron disease (MND) and two control cases were immunohistochemically examined using anti-bodies directed to neurofilament proteins (anti-Nf) and to heparan sulfate (HepSS-1). Variable numbers of spheroids were observed in the anterior horns in the MND cases. In one case of MND, one third to half of the remaining anterior horn cells contained conglomerate inclusions in their perikarya. These pathological structures were not encountered in the control cases. The immunohistochemical study revealed that both anti-Nf and HepSS-1 intensely labelled all spheroids and conglomerate inclusions in the MND cases. The colocalization of heparan sulfate with neurofilamentous accumulation suggests that heparan sulfate is required for the aggregation of neurofilaments, resulting in the formation of spheroids and conglomerate inclusions in MND.Supported in part by the Amyotrophic Lateral Sclerosis Association (USA)     

Familial motor neuron disease with Lewy body-like inclusions in the substantia nigra, the subthalamic nucleus, and the globus pallidus.

In a familial case of motor neuron disease (MND), 2 unusual features were noted in the necropsy. The first was a pallidoluysonigral degeneration, observed in only 4 other cases of MND and which was here asymptomatic. The second was the presence in degenerated spinal cord anterior horns and in degenerated basal ganglia of neuronal Lewy body-like inclusions stained by antibodies against ubiquitin.     

An autopsy case of frontotemporal dementia with severe dysarthria and motor neuron disease showing numerous basophilic inclusions

We report a clinicopathological study of a patient suffering from frontotemporal dementia (FTD) with severe dysarthria and concomitant motor neuron disease (MND). The patient was a 52‐year‐old woman with almost simultaneous emergence of severe dysarthria and FTD. The severe dysarthria subsequently evolved into anterior opercular syndrome. Motor neuron signs then emerged, and the patient developed akinetic mutism approximately 2 years after the onset of the disease. The patient died of pneumonia after a 7‐year clinical illness. Pathologically, severe and widespread degeneration in the frontal and temporal lobes, including the anterior opercular area, limbic system, basal ganglia, spinal cord and cerebellum, and frequent ubiquitin‐ and tau‐negative basophilic inclusions were observed. The pyramidal tracts and anterior horns of the cervical cord also showed marked degeneration. Cases showing basophilic inclusions reported so far have been divided into two groups: early onset FTD and MND with basophilic inclusions. Our case presented clinicopathological features of both FTD and MND, which suggests that cases showing basophilic inclusions may constitute a clinicopathological entity of FTD/MND.     

Numerous FUS‐positive inclusions in an elderly woman with motor neuron disease

We report an autopsy case of a 75‐year‐old Japanese woman with motor neuron disease (MND) showing numerous neuronal and glial inclusions immunostained with anti‐fused in sarcoma (FUS) antibody. At 73 years, she received a diagnosis of MND and died of respiratory insufficiency 2 years later. No mutation was found in all exons of the FUS gene. Neuropathological examination revealed a reduced number of anterior horn cells and degeneration of the pyramidal tracts. Neither Bunina bodies nor inclusions positive for ubiquitin/phosphorylated TAR DNA binding protein of 43 kD (pTDP‐43), such as skein‐like or round inclusions, were observed. However, basophilic inclusions (BIs) were frequently observed in the remaining neurons of the anterior horns, facial nuclei, hypoglossal nuclei, vestibular nuclei, dentate nuclei and inferior olivary nuclei. In an immunohistochemical analysis, the BIs showed strong immunoreactivity with anti‐FUS and anti‐ubiquitin‐binding protein p62 (p62) antibodies. The nuclear staining of FUS was preserved in some neurons with FUS‐positive inclusions, and a few FUS‐positive glial inclusions were found. FUS‐positive inclusions were more common than p62‐positive inclusions in some anatomical regions, and in some neurons, p62 immunoreactivity was observed in only parts of the BIs. These results suggest that BI formation and TDP‐43 aggregation have different pathogenic mechanisms, and FUS may play an important role in the pathogenesis of MND with BIs. This patient has the oldest reported age of onset for MND with BIs, and clinical features observed in this patient were indistinguishable from those of classic sporadic MND. Therefore, we consider that the age of onset and clinical features of FUS‐related disorders may be variable.     

Evidence for pathological involvement of the spinal cord in motor neuron disease-inclusion dementia

Fronto-temporal dementia (FTD), characterised pathologically by ubiquitinated inclusions in the hippocampal dentate fascia and fronto-temporal cortex, may develop in association with motor neuron disease (MND). However, FTD with identical pathological hallmarks may occur in isolation and has been termed motor neuron disease-inclusion dementia (MND-ID). We studied the pathology of three cases of MND-ID including the spinal cord, which has not previously been examined in this condition. The ages of the patients at death were 53, 70 and 68 years and the onset of FTD 10, 15 and 9 years before death. Neuropathological findings in all cases included micro-vacuolation in cortical layer II and ubiquitinated intraneuronal inclusions in fronto-temporal cortex and hippocampal dentate fascia. One case showed unusual basophilic, ubiquitinated neuronal cytoplasmic inclusions in the brain stem. Qualitative assessment of the spinal cord was normal in two cases, while the third showed mild pallor of the lateral cortico-spinal tracts and ubiquitinated inclusions in motor neurons typical of MND. Morphometry did not reveal any significant loss or decrease in size of anterior horn motor neurons. The results of this study are consistent with the hypothesis that the pathological changes of pure MND and MND-ID form a spectrum and demonstrate that pathological involvement of the motor system may occur in MND-ID without clinical evidence of MND.     

Gallyas-positive argyrophilic and ubiquitinated filamentous inclusions in rapidly progressive motor neuron disease: immunohistochemical and electron microscopic studies

In an autopsy case of sporadic rapidly progressive lower motor neuron disease (MND), Gallyas-positive argyrophilic and ubiquitinated filamentous intracytoplasmic inclusions were found in the neurons. Clinically, 7 months prior to death, a 68-year-old woman experienced a history of rapidly progressive muscle weakness of all four extremities and bulbar sign, without sensory and autonomic disturbance. Two months later, she became unable to stand or walk. Four months after onset, she needed respiratory support, and subsequently died due to cardiorespiratory arrest. Neuropathological examinations revealed neuronal loss and associated gliosis in the lower motor neurons, except for ocular motor nuclei, Clark’s column, and accessory cuneate nucleus, and tract degeneration was observed in the middle root zone of the posterior column and spinocerebellar tract. No Bunina bodies or Lewy body-like hyaline inclusions were found in the anterior horns. Gallyas-positive argyrophilic filamentous inclusions were found in the lower motor neurons and in nerve cells of the Clark’s column, intermediate zone, posterior horn and accessory cuneate nucleus. These were positive with anti-ubiquitin antibody but negative with anti-tau (tau-2 and AT8) and neurofilament antibodies. Electron microscopic examinations disclosed randomly arranged tubular-like filamentous profiles, with a diameter of 12–14 nm, sometimes with amorphous granules in the perikaryon. This is the first report on the Gallyas-positive argyrophilic and ubiquitinated filamentous inclusions in neurons in MND. Received: 23 October 1998 / Revised: 3 September 1999 / Accepted: 19 October 1999     

Sporadic lower motor neuron disease with Lewy body-like inclusions: a new subgroup?

Summary A sporadic case of lower motor neuron disease with Lewy body-like inclusions is presented. A woman of 69, 6 months before death, had a history of muscle weakness and atrophy of the four extremities. Neuropathological examination revealed neuronal loss and associated gliosis in the anterior horns of the whole spinal cord. The cytoplasm of some of the remaining neurons contained Lewy body-like inclusions, Bunina bodies, or both. Spheroids and cordlike thickenings of cell processes were also observed in the anterior horns. A few neurons showed argentophilia of the cytoplasm. No tract degeneration was detectable in the white matter of the spinal cord. The present case and two reported similar cases may constitute a new subgroup of motor neuron disease.Supported in part by NIH Grant no. 2 P50 NS 11605-09     

Motor neuron disease: quantitative morphological and microdensitophotometric studies of neurons of anterior horn and ventral root of cervical spinal cord with special reference to the pathogenesis.

Spinal anterior horn and ventral roots from C6 of spinal cord 6 patients with motor neuron disease (MND) and those from 6 controls were studied morphologically and biochemically, using microscopic observation, morphometry and microdensitophotometry. Spinal anterior horns in MND showed various kinds of morphological changes in nerve cells, and a significant decrease in cellular, nuclear and nucleolar cross-sectional areas in normal and abnormal cells. Microdensitophotometry revealed a significant decrease in the cellular RNA content, of both large cells and small cells, and also of histologically normal appearing cells and abnormal cells. Those findings point to an abnormality of RNA synthesis which precedes the earliest light microscopic changes seen in nerve cells. The cross-sectional areas of myelinated fibers and axons of spinal ventral roots in MND cases showed a significant decrease in the numbers of both total myelinated fibers and large axons. The abnormalities in myelinated fibers and axons of spinal ventral roots in MND cases might be secondary to those in both large nerve cells and small ones of spinal anterior horns in most MND cases and/or primary in some cases.     

TDP-43 in differential diagnosis of motor neuron disorders

Motor neuron disorders are clinically and pathologically heterogeneous. They can be classified into those that affect primarily upper motor neurons, lower motor neurons or both. The most common disorder to affect both upper and lower motor neurons is amyotrophic lateral sclerosis (ALS). Some forms of motor neuron disease (MND) affect primarily motor neurons in the spinal cord or brainstem, while others affect motor neurons at all levels of the neuraxis. A number of genetic loci have been identified for the various motor neuron disorders. Several of the MND genes encode for proteins important for cytoskeletal stability and axoplasmic transport. Despite these genetic advances, the relationship of the various motor neuron disorders to each other is unclear. Except for rare familial forms of ALS associated with mutations in superoxide dismutase type 1 (SOD1), which are associated with neuronal inclusions that contain SOD1, specific molecular or cellular markers that differentiate ALS from other motor neuron disorders have not been available. Recently, the TAR DNA binding protein 43 (TDP-43) has been shown to be present in neuronal inclusions in ALS, and it has been suggested that TDP-43 may be a specific marker for ALS. This pilot study aimed to determine the value of TDP-43 in the differential diagnosis of MND. Immunohistochemistry for TDP-43 was used to detect neuronal inclusions in the medulla of disorders affecting upper motor neurons, lower motor neurons or both. Medullary motor neuron pathology also was assessed in frontotemporal lobar degeneration (FTLD) that had no evidence of MND. TDP-43 immunoreactivity was detected in the hypoglossal nucleus in all cases of ALS, all cases of FTLD-MND and some of cases of primary lateral sclerosis (PLS). It was not detected in FTLD-PLS. Surprisingly, sparse TDP-43 immunoreactivity was detected in motor neurons in about 10% of FTLD that did not have clinical or pathologic features of MND. The results suggest that TDP-43 immunoreactivity is useful in differentiating FTLD-MND and ALS from other disorders associated with upper or lower motor neuron pathology. It also reveals subclinical MND in a subset of cases of FTLD without clinical or pathologic evidence of MND.     

FKBP12 immunoreactivity in the human spinal cord of motor neuron disease patients

We investigated the FKBP12 immunoreactivity in the spinal cord of neurological controls and motor neuron disease (MND) patients. In the neurological controls, the spinal neurons were markedly stained with antihuman FKBP12 (N‐19 and C‐19) antibodies. FKBP12 immunoreactivity was associated with lipofuscin in formalin‐fixed paraffin‐embedded samples. In an electron microscopic view, the 10‐nm colloidal gold particles labeled by the anti‐FKBP12 (N‐19) antibody were present on the lipofuscin of the spinal anterior horn neurons. In the MND cases, atrophic neurons with an abundance of lipofuscin granules in the anterior horns of the spinal cord were mildly stained with the anti‐FKBP12 (N‐19 and C‐19) antibodies. Normal‐appearing neurons, inclusion‐laden neurons and chromatolytic neurons of MND cases were weak or negatively stained with anti‐FKBP12 (N‐19) antibodies. These findings suggest that FKBP12 (N‐19) may decrease in the early stages of degeneration in MND. Complexes of FKBP12 and ligands were reported to have neuroprotective and/or neuroregenerative properties. It is speculated that the decrease in FKBP12 (N‐19) plays some causative role in the development of neurodegeneration in MND. Further investigation of FKBP12 and ligands may help elucidate the pathogenesis of MND.     

泛素阳性包涵体在运动神经元病的表达

目的：探讨泛素阳性包涵体在运动神经病（MND）中枢神经系统的分布、成分及与神经细胞变性的关系。方法：对5例MND和9例非神经系统变性病对照患者脑和脊髓进行苏木素－伊红、快蓝和Bodian常规染色,抗－泛素、抗－tau蛋白、抗－胶质纤维酸性蛋白和抗－神经丝蛋白抗体免疫组化染色。结果：5例MND抗泛素免疫组化染色在其中4例细胞 质内发现单线－线团样包涵体、透明包涵体、路易体样包涵体和不规则包涵体、相应前角细胞存在轻中度变性。3例海马颗粒细胞内出现泛素阳性包涵体。1例患者脊髓前角细胞内少数泛素阳性包涵体抗神经丝蛋白染色也阳性,各种泛不阳性包涵体抗tau蛋白及胶质纤维酸性蛋白染色为阴性,结论脊髓前角细胞质内的泛素阳性包涵体是MND较为特异的免疫病理改变,不同类型包涵体之间可能存在一定的演变规律,与相应神经细胞的变性相关。少数泛素阳性包涵体含有神经丝蛋白成分,海马颗粒细胞内出现泛素阳性包涵休提示此病同时累及非运动系统,并可能 与MND临床上智能或精神异常有关。     

Ubiquitin immunohistochemistry of frontotemporal lobar degeneration differentiates cases with and without motor neuron disease

Frontotemporal lobar degeneration (FTLD) without tau pathology is clinically and pathologically heterogeneous. The present report describes the neuropathology of 52 brains with FTLD without tau pathology compared with 10 brains of amyotrophic lateral sclerosis (ALS) without dementia using ubiquitin immunohistochemistry. The 52 cases were classified into 47 cases of FTLD with motor neuron disease (MND)-type inclusions but without MND (FTLD-MNI), three cases of FTLD with MND (FTLD-MND), and two cases of dementia lacking distinctive histopathology (DLDH) based on the features of ubiquitin-immunoreactive (ubiquitin-ir) structures in the caudate, frontotemporal cortices and dentate fascia, and presence or absence of neuronal loss in lower motor neurons. Many ubiquitin-ir neuronal inclusions and neurites in the caudate nucleus, frontotemporal cortices, and ubiquitin-ir crescent-or ring-shaped neuronal inclusions in the dentate fascia characterized FTLD-MNI. Ubiquitin-ir neuronal intranuclear inclusions (NII) were observed in 26 of 43 cases and associated with many neurites in the caudate nucleus as well as a familial history in most cases. A subset of cases had Pick-body-like inclusions in the dentate fascia and caudate nucleus with paucity of neuritic pathology and no NII; another had crescent-shaped inclusions in the dentate fascia and neuritic pathology with NII in the caudate. FTLD with MND was characterized by a few or no ubiquitin-ir inclusions in the caudate nucleus and frontotemporal cortices and ubiquitin-ir granular inclusions in the dentate fascia, as well as loss of lower motor neurons. These features were similar to ALS, but different from FTLD-MNI. The findings suggest that FTLD-MNI has a different pathogenesis from FTLD-MND and ALS.     

Immunohistochemical and ultrastructural study of basophilic inclusions in adult-onset motor neuron disease

We immunohistochemically and ultrastructurally studied basophilic inclusions (BI) in a patient with adult-onset sporadic motor neuron disease (MND). BI were frequently observed not only in degenerated anterior horn cells, such as central chromatolytic neurons, but also in normal-appearing large anterior horn neurons. They had various shapes, round, elliptical or irregular, and occasionally they had distinct basophilic rims. They also varied in size. There were no halos around them nor core in their centers. Immunohistochemically, some BI were immunostained for ubiquitin or SOD1, but BI were not immunoreactive with anti-phosphorylated neurofilament (SMI 31), phosphorylated tau, cystatin C or Golgi (MG-160) antibodies. Ubiquitin-positive skein-like inclusions (SI) were occasionally observed in the somata of anterior horn neurons. Ultrastructurally, BI consisted of filamentous structures associated with granules, which were attached to thick filaments. The thick filaments were straight without constriction or side arms and their diameter was twice that of the neurofilaments. BI occasionally contained tubular structures among the granule-associated filaments. The granulo-filamentous profiles varied from being compactly arranged to being more loosely packed. The structure of BI resembles that of the Lewy body-like hyaline inclusions (LBHI) observed in sporadic MND patients. Bundles of filaments resembling SI, which were composed of compactly packed filaments without fine granules running parallel to the longitudinal axis, were frequently observed inside or at the periphery of BI, and occasionally clustered in the perikarya. Each filament measured approximately 15-25 nm in diameter, and a bundle of these grouped filaments was sometimes surrounded by a unit membrane. We also occasionally observed in-between structures of BI and bundles of filaments resembling SI. These findings suggest a certain relationship between BI, SI and LBHI in the pathomechanism of BI development. Further studies are needed to elucidate whether sporadic adult-onset MND characterized by BI forms a different subtype of MND.     

Ubiquitin-only intraneuronal inclusion in the substantia nigra is a characteristic feature of motor neurone disease with dementia

Two types of ubiquitinated inclusions have been described in motor neurone disease (MND). (1) Skein or globular ubiquitinated inclusions in the motor neurones (more frequently in the lower motor neurones). This is a characteristic feature of all motor neurone disease categories. (2) Dot-shape or crescentric ubiquitinated inclusions in the upper layers of cortex and dentate gyrus described in cases of motor neurone disease with dementia (DMND). We investigated the substantia nigra (SN) in MND cases; two cases of motor neurone disease inclusion body (MND-IB) dementia, six cases of DMND, 14 cases of MND (including one case from Guam and two cases of familial SOD1 mutation), four cases of Parkinson's disease (PD), and 10 cases of age-matched normal controls. SN and spinal cord sections were stained with ubiquitin (alpha-synuclein, tau, PGM1, SMI-31 and SOD1 antibodies). The neuronal density in SN was quantified by using a computer-based image analysis system. Four out of six DMND cases showed rounded ubiquitin positive inclusions with irregular frayed edges, associated with neuronal loss, reactive astrocytosis and a large number of activated microglia cells. These inclusions are negative with antibodies to (alpha-synuclein, tau, SMI-31 and SOD1). The SN in cases from MND-IB dementia and MND showed occasional neuronal loss and no inclusions. The ubiquitin-only inclusions in SN of DMND cases are similar (but not identical) to the ubiquitinated inclusions described previously in the spinal cord of MND cases and are distinct from Lewy bodies (LBs). The degeneration of SN is most likely a primary neurodegenerative process of motor neurone disease type frequently involving the DMND cases. MND disease is a spectrum and multisystem disorder with DMND located at the extreme end of a spectrum affecting the CNS more widely than just the motor system.     

Ubiquitin immunohistochemistry suggests classic motor neuron disease, motor neuron disease with dementia, and frontotemporal dementia of the motor neuron disease type represent a clinicopathologic spectrum

One of the characteristic pathologic changes in classic motor neuron disease (MND) is the presence of ubiquitin-immunoreactive (ub-ir) inclusions in the cytoplasm of lower motor neurons. In addition, cases of MND with dementia (MND-d) also have ub-ir neuronal cytoplasmic inclusions and dystrophic neurites in extramotor neocortex and hippocampus. Although this extramotor pathology is a highly sensitive marker for dementia in MND, similar changes are found in a subset of patients with frontotemporal dementia (FTD) with no motor symptoms (FTD-MND type). The purpose of this study is to more fully describe and compare the pattern of ub-ir pathology in these 3 conditions. We performed ubiquitin immunohistochemistry on postmortem tissue, representing a wide range of neuroanatomic structures, in cases of classic MND (n = 20), MND-d (n = 15), and FTD-MND type (n = 15). We found the variety of morphologies and the anatomic distribution of ub-ir pathology to be greater than previously documented. Moreover, the degree of overlap suggests that MND, MND-d, and FTD-MND type represent a spectrum of clinical disease with a common pathologic substrate. The only finding restricted to a specific subgroup of patients was the presence of ub-ir neuronal intranuclear inclusions in some cases of familial FTD.     

Expression of FKBP12 and ryanodine receptors (RyRs) in the spinal cord of MND patients.

We investigated the FKBP12 and ryanodine receptor (RyR) immunoreactivity (IR) in the spinal cords of neurological controls and patients with motor neuron disease (MND). In the neurological controls, the cytoplasm of the spinal anterior horn neurons was stained with anti-FKBP12 antibodies and anti-RyR (type 1 and type 2) antibodies. In the MND cases, the residual neurons in the anterior horn of the spinal cord showed IR for RyR (type 1 and 2) antibodies, while weak IR for anti-FKBP12 antibodies was comparable to that of controls. The numbers of neurons recognized with the anti-FKBP 12 or anti-RyR (type 1 and 2) antibodies were counted in the anterior horn of spinal cords from the MND cases and neurological controls. Frequency of neurons stained with anti-FKBP 12 antibody was significantly decreased in the MND cases compared to that in controls (48.7+/-23.2%, 71.0+/-18.5%, respectively, mean+/-SD, p<0.0005). In the MND cases, numbers of normal-appearing, chromatolytic neurons showing IR to anti-FKBP12 (N19) antibody were significantly decreased compared to those in the controls. Immunoreactivities to anti-RyR antibodies (type 1and 2) in MND cases were present and there was no difference compared to those of the controls. Neurons in the spinal cord anterior horn of Kii-ALS cases with prolonged clinical duration were immunostained with both anti-FKBP12 and anti-RyR (type 1 and 2) antibodies similar to that in the controls. The anterior horn neurons of MND cases of short clinical duration showed absent IR to FKBP 12 antibody but present IR to RyR (type 1 and 2) antibodies. The present result suggests that FKBP12 IR was decreased in the MND cases with short clinical duration. RyR (type 1 and 2) is a major component of the intracellular calcium channel, which mediates calcium-induced calcium release. FKBP12, which is an endogenous ligand for RyR, stabilizes the calcium channels preventing calcium leakage in the absence of receptor activation. Imbalance between FKBP12 and RyR IR may play an important role in degeneration due to MND. Further study of the correlation between RyR and FKBP12 should contribute to clarifying the mechanisms of neurodegeneration in MND, including calcium-induced neuronal loss.     

The relationship between extramotor ubiquitin-immunoreactive neuronal inclusions and dementia in motor neuron disease

Dementia is thought to be an uncommon complication of motor neuron disease (MND). In addition to the characteristic motor system degeneration, pathological studies of MND patients with dementia have demonstrated changes in extramotor cortex; ubiquitin-immunoreactive inclusions are present in neocortical layer II neurons and hippocampal dentate granule cells. To examine how specifically this pathology is associated with dementia in MND, we performed ubiquitin immunohistochemistry on sections of hippocampus, prefrontal and temporal neocortex from 29 cases of MND, 10 with dementia and 19 with no clinical history of cognitive impairment. All cases with dementia had numerous ubiquitin-positive inclusions in dentate granule cells, whereas involvement of the neocortex was more variable. Six (32%) of the nondemented cases had ubiquitin pathology, which was similar to the demented cases in its morphology and distribution but of slightly less severe degree. These findings demonstrate that, although ubiquitinated inclusions in extramotor cortex are a consistent finding in MND with dementia, they are also common in MND in the absence of documented cognitive abnormalities. Such cases may either represent a subclinical stage of pathology or indicate that cognitive dysfunction is an underrecognized complication of MND.     

Excitatory amino acid transporter 1 and 2 immunoreactivity in the spinal cord in amyotrophic lateral sclerosis

The spinal cord of 20 patients with amyotrophic lateral sclerosis (ALS) and 5 patients with lower motor neuron disease (LMND) were investigated immunohistochemically using anti-human excitatory amino acid transporter 1 (EAAT1) and EAAT2 antibodies which are the astrocytic transporters. The purpose of the study was to examine relationships between EAAT1 and EAAT2 immunoreactivity and degeneration of anterior horn neurons. Specimens from 20 patients without any neurological disease served as controls. In controls, spinal cord gray matter was densely immunostained by antibodies, whereas the white matter was generally not immunostained. In motor neuron disease (MND) patients, EAAT1 immunoreactivity was relatively well preserved in the gray matter despite neuronal loss of anterior horn cells. On the other hand, EAAT2 immunoreactivity in anterior horns correlated with the degree of neuronal loss of anterior horn cells: in the patients with mild neuronal depletion, anterior horns were densely immunostained by the antibody, whereas in the patients with severe neuronal loss, EAAT2 expression was markedly reduced. Degenerated anterior horn cells frequently showed a much denser EAAT1 and EAAT2 immunoreactivity around the surface of the neurons and their neuronal processes than that observed in normal-appearing neurons. There was no difference in the expression of EAAT1 and EAAT2 immunoreactivity between LMND and ALS patients. These findings suggest that in the early stage of degeneration of anterior horn cells, EAAT1 and EAAT2 immunoreactivity is preserved in the astrocytic foot directly attached to normal-appearing neurons, whereas levels of EAAT1 and EAAT2 protein rather increase in the astrocytic foot directly attached to degenerated anterior horn neurons; the latter effect most probably reduces the elevated glutamate level, compensates for the reduced function of astroglial glutamate transporters, or represents a condensation of EAAT1 and EAAT2 immunoreactivity secondary to loss of neurites and greater condensation of astrocytic processes. Thus, we demonstrate a difference in EAAT1 and EAAT2 immunoreactivity in different stages of progression in ALS, as a feature of the pathomechanism of this disease. Received: 8 September 1999 / Revised, accepted: 28 October 1999     

Ubiquitin and ubiquitin‐related proteins in the brains of patients with atypical Pick's disease without Pick bodies and dementia with motor neuron disease

Nine cases of atypical Pick's disease without Pick bodies (aPiD) and seven cases of dementia with motor neuron diseases (D‐MND) were compared using immunohistochemistry of ubiquitin (ub) and ub‐related proteins. All cases showed rostral‐dominant atrophy in the temporal and frontal lobes, although the degree of atrophy with neuronal loss was much more severe in the aPiD cases. In both aPiD and D‐MND cases, ub‐positive and tau‐negative structures were found mainly in the hippocampal dentate gyrus and cerebral cortex. Granular cells of the dentate gyrus showed similar ub‐positive intraneuronal inclusions in both cases. In the aPiD cases, most of the ub‐positive cortical structures were ub‐positive dendrites in layers II‐IIIab and layers V‐VI, although some neurons also showed diffuse ub‐positive staining in the cytoplasm. In the D‐MND cases, some neurons showed ub‐positive inclusions in layers II‐IIIab, and ub‐positive dendrites were unremarkable. The number of ub‐positive neurons and dendrites in relation to the degree of neuronal loss in the cerebral cortex were then evaluated. The number of ub‐positive neurons in the regions showing very mild to mild neuronal loss was significantly greater in the D‐MND cases than in the aPiD cases. However, in the aPiD cases, the number of ub‐positive neurons was significantly greater in the regions showing moderate neuronal loss. When double‐immunostained, almost all ub‐positive structures were positive for ub‐binding protein p62. Some ub‐positive or negative neurons in the cerebral cortex were immunostained with anti‐ub ligase (Parkin) and anti‐ub C‐terminal hydrolase (UCH‐L1) antibodies. Granular cells of the dentate gyrus were weakly positive for UCH‐L1. There could be some differences in the mechanism by which neurons in the cerebral cortex accumulate ub between aPiD and D‐MND.     

Lewy body-like hyaline inclusions in sporadic motor neuron disease are ubiquitinated

Summary Round eosinophilic hyaline inclusion bodies with halos in the somata of anterior horn cells from a case of sporadic lower motor neuron disease (MND) were intensely immunostained with the monoclonal anti-ubiquitin antibody (DF2). A few similar, DF2-positive inclusions were also observed in the nerve cell processes of anterior horn cells or in the neuropil. Most inclusions showed intense homogeneous staining of the entire inclusion, whereas a few had intense staining of their periphery with no or pale staining of the central areas. Other DF2-positive structures in the somata of anterior horn cells included cytoplasmic granular structures, eosinophilic thread-like or reticular structures, and small eosinophilic profiles different from Bunina bodies. The DF2-staining intensity of Bunina bodies and spheroids did not exceed the background level. These results suggest that ubiquitination is associated with a pathological process of anterior horn cell degeneration in this MND case.